41: Iodine – induced Thyrotoxicosis

Iodine – induced Thyrotoxicosis ($4,260)

The soil and water of Tasmania, Australia’s island state, is naturally low in iodine. As a result, so too are locally grown foods, making iodine deficiency a potential hazard for the Tasmanian population.

The incidence of thyrotoxicosis in northern Tasmania rose significantly in 1964, two years before an epidemic of iodine-induced thyrotoxicosis was precipitated by the addition of iodate to bread to prevent goitre. Each time older patients accounted for most of the increase. The 1964 increase was probably iodine-induced as the use of iodophor disinfectants on dairy farms, which causes iodine residues in milk, began in 1963, and a fall in the prevalence of goitre in young children suggested an increase in dietary iodine at about that time. A further small increase in thyrotoxicosis in 1971 may also have been iodine-induced as it followed an extension of the use of iodophors.

Dr Vidor’s extensive writings and historical data on his research were unfortunately stolen from a car, and this grant will assist in the re-compiling of data from old patient records still at Launceston General Hospital.